Entecavir should not be taken two months after its expiration date. This is because after the expiration date, the drug may be degraded, thus producing impurities, leading to a decrease in the therapeutic effect of the drug, thus delaying the treatment of the disease. In addition, it may also cause new harm to the body, because expired drugs may lead to increased toxicity, which may cause allergy in the light of taking, or may cause poisoning or even death. Since entecavir tablets are mainly indicated for the treatment of chronic adult hepatitis B with persistent elevation of serum alanine aminotransferase, active lesions shown by liver histology, and active viral replication, the medication should be discontinued when it is found to be expired. Patients taking entecavir should follow the doctor’s instructions to take the correct medication, should not miss or stop taking, if found that the drug is about to expire, should be in advance to find a doctor to re-prescribe, so as not to cause the drug discontinuation, which will lead to the occurrence of resistance and weakening of the therapeutic effect.